Pressing apparatus



March 5, 1946. B; A. EVANS PRESS ING APPARATUS Filed Nov. 30, 1944 jEi'j527215;? z/Efis Patented Mar. 5, 1946 UNITED STATES PATENT OFFICE.

PRESSING APPARATUS Benjamin A. Evans, Cuyahoga Falls, Ohio, assign or toTheB. F. Goodrich Company, New York, N. Y., a corporation of New YorkApplication November 30, 1944, Serial No. 565,897

4 Claims.

This invention relates to pressing apparatus such as platen presses andis especially useful where presses having platens of great area are tobe used in vulcanizin sheet material such as ber and other materialsstick to the platens and become permanently attached thereto while somematerials employed corrode the platen, requiring frequent cleaning andpolishing of the platen faces. As the platens are often of great area ithas been customary to employ portable sanding and polishing apparatus toclean and polish the platens in place. Frequent cleaning and polishinghas sometimes resulted in departure from a true surface so that thebelts or other articles vulcanized therebetween have been of non-uniformthickness.

As belts and other sheet material vulcanized in presses must depend fortheir surface characteristics upon the characteristics of the surfacesagainst which they are vulcanized, a highly finished surface Will'produce a highly finished article, whereas an irregular or dirty surfacewill produce an article having an inferior surface.

Heretofore it has been necesary to remove the platens from a press atfrequent intervals and return them to a machine shop for resurfacin withloss of press time, and, with repeated machining, considerable loss ofstrength of the platens.

The present invention has for one of its objects to avoid the foregoingand other difficulties.

Other objects are to provide a removable platen surface, to providereduction of corrosion, to provide a more highly finished vulcanizedarticle, and to provide for convenience of mold maintenance.

These and other objects will appear from the following description andthe accompanying drawing.

Of the drawing,

Fig. 1 is a side elevation of a hydraulic belt press constructed in.accordance with and embodying the invention, portions being broken away,

Fig. 2 is a cross-sectional view thereof taken on line 2-2 of Fig. 1,

Fig. 3 is a detail view of a modified form of the invention, parts beingbroken away.

Referring to the drawing, the numeral l0 designates the upper or fixed'platen of a hydraulic belt press supported by tension rods H. Themoveable or lower platen I 2 rests upon a series of rams I3 each fittedin a cylinder M, the rams being operated in unison by admission of fluidunder pressure simultaneously to all of the cylinders and lowered bysimultaneous draining of all the cylinders. The lower platen is guidedin its vertical movement by the tension rods H. The platens arechambered, as at l5, I6 for circulation of heating fluid, such as steam,and are .connected by swing joints l1, 18 to stationary piping (notshown) whereby steam or other heating fluid is circulated through theplatens at vulcanizing temperature.

For providing a highly polished corrosion-resistant surface over themoveable platen, a pair of laterally spaced-apart brackets 20 are fixedto one end of the platen and have aligned bearings for supporting ahorizontal winding shaft 2|. A drum 22 is fixed to the shaft. A ratchetwheel 23 is also fixed to the shaft in position to engage a pawl 24pivoted upon one of the brackets 20. At the opposite end of the platen,similar laterally spaced brackets 25 support a horizontal shaft 26having a drum 2! and a ratchet wheel 28 fixed thereto.

A band 32 of highly polished corrosion-resistant metal, such asstainless steel, has one end secured, as by screws or clamps to thesurface of the drum 22 and the other end secured by similar means to thedrum 2'! and extends from one drum to the other across the face of theplaten to provide a removable vulcanizing surface thereover. The shafts2| and 26 are squared at their ends to receive a crank handle 30 whichis interchangeable, the crank havin a squared opening to engage theshaft ends. The ratchet wheels 23, 28 are of opposite hand and soarranged that the pawl 24 normally prevents rotation of drum 2| in acounter-clockwise direction and pawl 3| which engages ratchet wheel 28normally prevents rotation of drum 21in a clockwise direction. Eitherpawl may be displaced from its nor. mal position where it engages aratchet by a handle fixed thereto. The arrangement is such that themetalband may be tensioned by rotating either of the shafts with the pawlsengaging the ratchets and will be held in tensional relation by theratchets and pawls.

The band 32 may be merely long enough to extend from one drum to theother, in which case the drums are used merely to tension the band, orthe band. may be several times such length in which case the excesslength is stored on the drums and the band may be shifted from time totime to present successive portions thereof for use between the pressplatens. Where the band is only slightly more than the length of theplatens, one of the winding drums may be dis-.

32 has its end clamped between the clamp bars by the bolt 37. 1

A similar band 38 of polished corrosion-resistant metal is secured overthe face of the upper platen In, its one end being secured either by atensioning drum 39 having a ratchet wheel 40 held against turning in onedirection by a pawl 4| as'shown in Fig. 1 or by clamp means such as-thatof Fig. 3. The other end of the band 38 is secured to a drum 42 at theopposite end of the press. Drum 42 is fixed to a shaft 43 having asquared rod for receiving a crank 44. A ratchet 45 secured to shaft 43is prevented from rotating in one direction by a pawl 46 pivotallysecured to the platen and having a handle 41 for displacing it when thedrum is to be turned in the normally locked direction.

In use, the bands of corrosion-resistant metal are tensioned across theface of the platens preferably after the press platens have been heatedto the desired temperature. The belt or other sheet to be vulcanized isthen drawn through the press and the lower platen is raised to press thesheet between the metal bands. Should the bands become dirty, they maybe quickly removed from the press and replaced by others, or, where thebands are longer than the press, they may be wound from one set of drumsto the other to present a clean surface for use and then tensioned. Whena band becomes soiled, it may be removed and cleaned by passing itthrough cleaning baths or polishing machines without delaying operationof the press.

Variations may be made withoutdeparting from the scope of the inventionas it is defined by the following claims.

I claim:

' 1. Pressing apparatus comprising a pressing member, a removablepressing sheet of corrosion-resistant metal upon a face thereof, andmeans on said pressing member for tensioning said sheet in the directionof said face.

2. Pressing apparatus comprising a pressing member, a removable pressingsheet of stainless steel upon a face thereof, and means on said pressingmember for tensioning said sheet in the direction of said face.

3. Pressing apparatus comprising a pressing member, a removable pressingsheet of corrosion-resistant metal upon a face thereof, means forsecuring one end of the sheet to the pressing member, and a tensioningdrum at the opposite end of the member for securing the opposite end ofsaid sheet and presenting a tensioned portion thereof across saidmember.

4. Pressing apparatus comprising a press platen. winding drums atopposite ends of the platen, a pressing sheet of corrosion-resistantmetal having a length greater than said platen. the ends of said sheetbeing secured about said drums. means for rotating said drums to tensionsaid sheet across said platen. and means for looking saiddrums againstrotation in a direction tending to reduce the tension of said sheet.

BENJAMIN A. EVANS.

